Tubular skylights have been provided for illuminating rooms inside buildings with natural light. Not only do tubular skylights thus save electricity and, concomitantly, are environmentally benign, but they illuminate rooms in a pleasing way using natural sunlight instead of 60 cycle electric light. An example of a commercially successful tubular skylight is disclosed in U.S. Pat. No. 5,099,622, assigned to the same assignee as the present invention and incorporated herein by reference.
A tubular skylight includes a roof-mounted, dome-like transparent cover. The cover is mounted on the roof of a building by means of a flashing. An internally reflective tube depends downwardly from the flashing to the ceiling of the room sought to be illuminated, and the bottom of the tube is covered with a disk-shaped light diffuser that is positioned at the ceiling.
A roof-mounted flashing typically includes a curb, the top of which is covered by the dome and the bottom of which engages a downwardly-depending skylight tube. A flat skirt is typically formed around the bottom of the curb, with the skirt extending radially away from the curb. The skirt is fastened to the roof such that the flashing provides an upper support for the skylight.
Past methods of making skylight flashings generally require a flat piece of sheet metal to be bent into the desired frusto-conical shape, with the opposed sides of the pieces that meet each other being welded of otherwise fastened together along a seam. Such seams, unfortunately, are unsightly and can fail, allowing dust to enter the skylight and degrade its light transmitting capabilities. Furthermore, the flat skirts, being made of sheet metal, ordinarily are not exceptionally strong. Consequently, the skirts can easily bend, warp, or otherwise become deformed, thereby interfering with the proper engagement of the flashing with a roof. The present invention recognizes the above problems and provides the below-disclosed solutions to one or more of the problems noted herein.